1. Field of the Invention
The present invention relates generally to a camera module, and particularly, to an apparatus and a method for controlling operation of a camera module having an auto-focusing device installed therewith.
2. Description of the Related Art
Recently, portable devices mounted with a small and light camera module increase with the development of the technique related to a digital camera. This type of camera module generally adopts the auto-focusing function, which corrects the out-focusing caused by a distance from a subject when taking a picture.
The auto-focusing function is implemented by a forward and backward movement of a lens module along an optical axis. Generally, the drive force by means of electric current is used when the lens module moves in a direction, while the attraction force between a magnetic member and a metallic yoke is used when the lens module moves in the other direction, wherein the magnetic member is attached to a side of the lens module and the metallic yoke is oppositely arranged to be spaced from the magnetic member.
Accordingly, when the lens module moves in a direction using the drive force by means of electric current, the large amount of electric current consumption is needed so as to overcome the attraction force between the magnetic member and the yoke.
Furthermore, when the lens module moves in the other direction, the moving speed of the lens module is slow because the movement of the lens module depends only on the attraction force between the magnetic member and the yoke, which leads to the delay in the auto-focusing function.